Think exfoliating products are just a sales gimmick? Dermatologists say they really do help you get a healthy glow on. Read on to learn how to make the most of a scrub…

Drugstore beauty aisles are full of products claiming to exfoliate skin, but many women don’t know how and when to scrub. Or what it actually does for complexions.

Turns out, it’s a key way to keep skin soft and glowing. Especially as we age.

Here’s why exfoliating helps: The top tier of skin (the epidermis) is made of layers of dead, flattened cells. Over roughly four weeks, these move from the bottom of the epidermis to its surface, where they naturally fall off, exposing newer, fresher-looking skin underneath.

By removing the topmost layer, exfoliating speeds up the skin’s shedding process, says New York City-based dermatologist Doris Day, M.D., author of Forget the Facelift (Avery).

But exfoliating too often or using the wrong products may dry out or irritate skin.

So how do you make sure you don’t rub skin the wrong way? Read on for the dermatologists’ top do’s and don’ts.

Do know what exfoliating does for your skin.A gentle scrubbing offers more than a temporary rosiness and softer, smoother skin.

Over the long term, regular exfoliation “can visibly minimize pores and rejuvenate the skin’s surface,” says Patricia Wexler, M.D., associate clinical professor of dermatology at Mount Sinai College of Medicine in New York.

Exposing fresher cells evens out texture and tone – including acne scars – and unclogs pores. And it makes pigmentation and fine lines less noticeable, because you’re removing some discolored, sun-damaged skin.

Exfoliating can also boost penetration of other skin products – those that moisturize or fight wrinkles, acne and discoloration. It also makes self-tanners look more natural and last longer.

Don’t think all exfoliants are created equal.Exfoliants fall into two categories: physical and chemical. To understand their differences, imagine a sink of dirty pots and pans. Both a scouring pad and dish soap will clean them, but in different ways.

Chemical, or liquid, exfoliants use a mild acid to dissolve the “glue” that binds dead cells to the skin’s surface, Day says. These include beta hydroxy acids (salicylic is one) and alpha hydroxy acids, such as glycolic and lactic.

Which is best for you? It depends on your skin type.

If you have extremely dry, sensitive or acne-prone skin, choose chemical exfoliants over grainy scrubs. The latter can be too abrasive, leaving skin inflamed and irritated.

Salicylic acid is particularly good for acne sufferers because “it exfoliates the surface layer of dead skin cells and cleanses away acne-forming bacteria,” Day says.

And whatever your skin type, use physical scrubs with ground fruit pits, nuts or shells only on your body, not your face. These may sound safe because they’re made with natural ingredients, but they can tear delicate facial skin with their harsh, jagged edges, exacerbating acne and other skin conditions.

Do know when to exfoliate.All skin types benefit from a good scrubbing, Wexler says.

“I advise all my clients to exfoliate regularly, no matter their skin condition – whether aging, acne-prone or sensitive – for optimum cell renewal and a glowing complexion,” she says.

But how often you exfoliate depends on your skin type. If your face is oily, exfoliate at least once a week.

Women with drier, more sensitive skin should stick to only once a week or every two weeks, Day advises.

Body parts like knees, elbows, ankles and feet can be rubbed and scrubbed every other day. That’s because skin is thicker in these areas and can tolerate more friction. Plus, dead, dry skin cells tend to pile up there.

But don't scrub if you have an active infection, cold sore, sunburn, extremely dry skin, redness or inflammation for any reason. Let skin heal before exfoliating or you may worsen the conditions.

Don’t overdo exfoliation.While a little can make a big difference in your complexion, over-exfoliating can damage skin, aggravating acne or increasing dryness.

Another common problem: Using too many exfoliants at once. It’s an easy mistake. How many times have you washed your face with a physical exfoliant (like a loofah or grainy scrub) and then applied a chemical exfoliant (a skin cream with alpha-hydroxy-acids)?

Do know how to exfoliate.Pretty much every body part can be exfoliated, but here are tips to make it more effective.

On your face, use a light hand and apply exfoliant to damp skin – it causes too much friction on dry skin.

Exfoliate your lips with a toothbrush, washcloth or an exfoliant made for lips to remove dry flakes and boost blood circulation.

Are You Skin-Care Savvy?The skin is a living, breathing organ, and what you don't know about taking care of it could keep your complexion from looking fantastic. If your skin-care knowledge could barely fill a pillbox, you need a refresher course. Do you know how to put your best face forward? Find out now with our skin-care quiz.

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